Steam-engine.



PATENTBD' AUG. 7, 1906.

W. R. EMERSON. STEAM ENGINE. APPLIOATION FILED JAN.16. 190s.

WILLIAM R. EMERSON, OF WASHINGTON, DISTRICT OF COLUMBIA.

STEAM-ENGINE.

Specification of Letters Patent.

Patented Aug. '7, 1906.

Application filed January 16j 1906. Serial No. 296.300-

To all whom, it may concern:

Be it known that I, WILLIAM R. EMERSON, a citizen of the United States, residing at Washington, in the District of Columbia, have invented certain new and useful Improvements in Steam-Engines; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this specification, and to the letters of reference marked thereon.

This invention relates to improvements in multiple-cylinder steam-engines, the inven tion being more especially applicable in connection with that type of multiple-cylinder 1 engines known as Brotherhood triple-cylinder engines, a fairly accurate description of i which may be foundv in United States Patent No. 145,719, granted December 23, 1873, to Peter Brotherhood.

The objects of the invention are to improve the construction and arrangement of the 1 Working parts, whereby wear due to friction is largely overcome, those parts subjected to friction being so formed that lubricant admitted with the steam or otherwise into the working areas will find its way to all of such surfaces.

A further object of the invention is to provide a structure which when assembled will maintain the parts in their proper relative ositions without the necessity of providing ocking or retaining devices such as are liable to'become loosened or to permit the parts to separate when subjected to hard usage.

A still further object of the invention is to provide a structure in which water or other non-compressible material trapped in the cylinders will not arrest the movement and cause a stoppage of the engine.

Referring to the accompanying drawings, Figure 1 is a sectional view taken centrally of the three cylinders and in a plane at right angles to the crank-shaft, the connectingrods being shown in elevation. Fig. 2 is a plan of the coupling block or head for connecting the rods and crank-shaft. Fig. 3 is an elevation at right angles to Fig. 2 with a art of the crankshaft and valve in place. Figs. 4 and 5 are elevations of one of the pins constituting the bearing and means for coupling the connecting-rods and coupling block or head together. Fig. 6 is an elevation of one of the connecting-rods looking at the same in a plane at right angles to the plane of Fig. 1. Fig. 7 is a transverse section through one of the pistons, showing the form of the connecting-rod, socket, and pin-recess. Fig. 8 is a detail section in a plane longitudinally of the shaft, showing the valve for controlling the passage of steam from the central chamber to the ends of the cylinders.

Similar letters of reference in the several figures indicate like parts.

In said drawings the three cylinders indicated by the letter A are grouped about a common center and preferably cast integrally.

with a crank-case B, which latter at one side is provided with a bearing for the crank-shaft C, having a crank D thereon, and at the opposite side said crank-case is provided with a head having inlet and exhaust ports leading out to the ends of the respective cylinders in the well understood manner. Working against the inner face of the head is a rotary valve E, having suitable exhaust and steam spaces e e, which will control communication with. the ends of the cylinders in the proper sequence to cause the reciprocatory movements of the pistons and the rotation of the crank-shaft through connections to be presently described. The valve is preferably rotated by the end of the crank D, which enters a recess therein or engages a shoulder thereon, as heretofore; but in the present instance the exhaust-passage extends longitudinally of the valve-stem E, preferably being formed by a slot E in one side of said stem, said passage thus constituting a duct which will insure the distribution of lubricant to the whole frictional surface of the valve-stem, thereby dispensing with the necessity of a special lubricating means for this portion of. the engine.

The pistons indicated by the letters G are preferably of the trunk variety, and the connecting-rods I-I extend well up into the pistons and are provided with eyes or bearings for the reception of transverse connectingpins I, mounted in pistons. The pins I, it will be noted from Fig. 7, are seated in the transverse openings in the pistons. Such openings, however, extend in from one side only of each piston, or they are reduced at the opposite side of the piston to a sufficient extent to form shoulders 9, against which the ends of the pins will abut. In operation it is designed that the engine shall be located or positioned with the shoulders g on the lower side of the piston, whereby said pins will be held in place by gravity and at the same time will not contact with or cause friction against the sides of the cylinders. The pins I are of smaller diameter than the eyes h, which encircle the same, the object of this construction being, first, to provide a rolling contactsurface between the pins and eyes, and thereby avoid as far as possible any wear due to friction; secondly, to form an opened space into which the steam will readily find its way for carrying lubricant to the pins, and, finally, to provide a looseness between the piston and the connecting-rods for a purpose which will be presently explained.

The inner ends of the connecting-rods H are jointed to the crank D by what I shall herein term a coupling-head. This coupling-head, generally speaking, is j ournaled 011 the crank-pin and carries three equally-spaced pins, to which the inner ends of the connecting-rods are jointed, respectively, By this construction a single extended bearing is formed on the crank-pin itself, and each connecting-rod is'provided with its own connecting-pin. In the preferred construction these parts are so constructed and assembled that each is retained in its proper position by the other, thereby dispensing with the necessity of employing special retaining devices.

By reference to Figs. 1 to 5 it will be seen that the coupling-head K is formed with a central opening k and three openings 7c, the latter constituting the bearings or sockets for the reception of the connecting-rod pins L. '(Shown in Figs. 4 and 5.) The central opening constitutes a socket for the reception of a removable sleeve K, which forms the direct bearing for the crank-shaft D. The central portions of the pinsL are cut away for the admission of the ends of the connecting-rods, and in assembling the parts the connecting-rods and pins are put in position before the sleeve K, and the latter when inserted will limit the inward movement of the connecting-rods to such an extent as to prevent them from escaping from the central recesses of the pins, and the longitudinal movements of the pins in their sockets will be prevented by the ends of the connecting-rods. In this preferred construction the bearing-surfaces are sub stantially knife-edge bearingsthat is to say, the pins are cut away centrally at each side to form knife-edges Zand the ends of the connecting-rods are provided with V- shaped bearings h, in which the knife-edges Z seat, although it will be understood that bearings such-as shown at the outer ends of the connecting-rods may be employed or knife-edge bearings may be employed at both ends of the connecting-rods; but, as before stated, in the preferred construction the knife-edge bearings are provided at the inner ends and rolling bearings at the outer ends of said rods.

The ends of the connecting-ro ds are preferably formed of a width to fit with some degree of accuracy into the slots or recesses formed for their reception in the pistons and coupling-head in order to prevent any wabbling movement of said links, or, in other words, to maintain the parallelism of the contact-points of the bearing-surfaces. In order to prevent any tendencyof the pins L to rotate in their sockets, the knife-edges Z are brought back to a point in proximity to the axial line of said pins, although in order to facilitate their initial adjustment and to prevent any possibility of accidental turning in their sockets they may be provided with spuds Z, adapted to enter grooves or recesses k in the coupling-head.

According to the well-understood principles covering the operation of this particular type of engine steam-is admitted to the crank chamber or space between the three pistons, thereby establishing a substantial balance of the parts under the influence of which no torque is exerted on the crank-shaft, and in order to disturb this balance steam is admitted to the outside of the pistons in succession, thereby producing a substantially uniform torque on the crank-shaft at all points in its rotation. As each piston reaches the extreme of its throw the valve will operate to admit the exhaust-steam to or from the outer end, and inasmuch as the pressure is always maintained on the inner sides of the pistons the connecting-rods are always in tension, and consequently there is no shake in the bearings between the said connecting-rods and pistons or between said connecting-rods and the coupling-head. The loose connections at these points, therefore, are not disadvantageous, as might be supposed, but result in a positive advantage both in the freedom of running and in the facility with which the working surfaces may be maintained at excessive speeds or under varying and hard usage. Furthermore, should water or noncompressible material be trapped in the ends of the cylinders the result will not be disastrous nor will the movement of the engine be materially interfered with, inasmuch as the loose connections will permit the pistons to come to rest before reaching the extreme outward limit of their throw, without binding or cramping against the crank, and so tending to prevent or retard its rotation.

An engine of this character does not require the use of a fiy-wheel, and in c0ntrolling its movement it is obvious that a throttle-valve may be used in the steam-supply pipe; but in the preferred arrangement the engine is controlled entirely by the exhaust, for which purpose it is preferred that the exhaust-pipe shall lead from the under head of the crank-case in substantial alinement with the stem of the valve and that a throttlevalve be located in the exhaust-pipe at a point in proximity to the engine. This arrangement permits of the parts being left in a static condition, but ready to move instanter when the pressure in the exhaust is relieved to a greater or less extent, and this is made possible by the fact that the engine is practically without packed joints of any character, the only possible point where there could be an escape of steam being around the crank-shaft itself, and the pres sure within the crank-case will ordinarily sufiice to maintain a steam-tight joint be tween the inner face of the head and the outer face of the crank without the use of packings.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, iS

1. In a multiple-cylinder engine wherein the power is applied to the crank-shaft only through tension on the connecting-rods, the combination with the radially-disposed cylinders, crank-case normally open to steam pressure, pistons, shaft and crank, of a coupling-head journaled and free to move angularly on the crank, connecting-rods all independently and freely pivotally connected with the coupling-head at all times and each pivotally connected with a piston, whereby the axes of the crankpin and pivotal connec tions of the working piston will automatically aline themselves.

2. In a multiple-cylinder engine, the com bination with the cylinders equally spaced about a common center, a crank-shaft and pistons in said cylinders, of connecting-rods between said. pistons and crank, said rods being pivotally connected and loose trans versely of their pivotal axes whereby the pistons may be arrested in their outward movement before reaching the extremes of their throw.

3. In a multiple-cylinder engine, the combination with the cylinders equally spaced about a common center, a crank-shaft and pistons working in said cylinders, of connecting-rods interposed between the pistons and crank, eyes on the outer ends of said connecting-rods and pins in the pistons of less ex? ternal diameter than the internal diameter of the eyes.

4. In a multiple-cylinder engine, the combination with the cylinders equally spaced about a common center, pistons working in said cylinders and a crank-shaft, of a couplinghead j ournaled loosely on the crank and having knife-edge pins mounted therein and links embracing and free to move transversely of said pins and pivotally connected with the pistons; substantially as described.

5. In an engine such as described, the combination with the cylinders, pistons, crankshaft and connecting-rods, of a couplinghead journaled on the crank-shaft and removable pins in said couplinghead having cut-away portions for the receptiom of the ends of the connecting-rods; substantially as described.

6. In a multiple-cylinder engine, the combination with the cylinders, pistons, crankshaft, and connecting-rods, of a coupling head having the pins for the reception of the inner ends of the connecting-rods and the central removable sleeve for holding said rods in place and constituting the journalbearings for the crank; substantially as de-' scribed.

7. In a multiple-cylinder engine, the combination with the cylinders, pistons, crankshaft, and connecting-rods, of the coupling head having the removable pins provided with central knife-edges for cooperation with the inner ends of the connecting-rods, and the central removable sleeve for limiting the movement of said connecting-rods and thereby preventing the escape of the pins; substantially as described.

8. In a multiple-cylinder engine, the combination with the cylinders equally spaced about a common center, pistons in said cylinders, a crank-shaft, connecting-rods pivotally connected with the pistons at their outer ends and having V-shaped bearings at their inner ends, of a coupling-head journaled loosely on the crank-shaft and pins mounted in said coupling-head and having knife-edges for cooperation with the V-shaped bearings at the inner ends of the connectingrods; substantially as described.

9. In a multiple-cylinder engine, the combination with the cylinders equally spaced about a common center, pistons in said cylinders, a crank-shaft, and connecting-rods pivotally connected with the pistons, of a rigid coupling-head journaled loosely on the crank and having recesses formed therein for the re ception of the inner ends of the connectingrods and transverse removable pins one for cooperation with and held in place by the bearing on said inner end of each of the con.

necting-rods; substantially as described.

10. In a multiple-cylinder engine wherein the power is applied to the crank-shaft only through tension on the connectingrods, the combination with the cylinders, pistons in said cylinders and crank-shaft, of a coupling head journaled loosely on the crank of the shaft and having knife-edge bearings thereon and connecting-rods pivotally connected with the pistons and each having a V-shaped bearing at the inner end loosely embracing one of the knife-edge bearings on the coupling-head; substantially as described.

WILLIAM R. EMERSON.

Witnesses:

ALEXANDER S. STEUART, THOMAS DURANT.

ITO 

